Recent advice on depression screening from the US Preventive Services Task Force (USPSTF) may lead to overtesting and overtreatment, according to some experts.
The advice - to screen all children aged 12 years and older and all adults for depression - contrasts with Britain and Canada which recommend against routine screening, and is one of several recommendations issued by the task force in the past few years that are far more liberal in promoting interventions.
In a special report published today, The BMJ Associate Editor Jeanne Lenzer asks whether the task force - widely respected for its independent, objective guidance on preventive services - is still a voice of caution.
Some task force recommendations rely on questionable research methodologies, writes Lenzer.
For example, Brett Thombs, professor of psychiatry at McGill University told The BMJ: "In the absence of any trial evidence that screening would benefit patients, there is real concern that these recommendations may lead to more harm than good."
However, Kirsten Bibbins-Domingo, current USPSTF chair and professor at the University of California, San Francisco, said: "We evaluate the available evidence around preventive services by assessing a variety of valid trial designs and rigorously examining studies for potential bias."
A second concern, says Lenzer, stems from the fact that USPSTF recommendations have been based on evidence reviews that have not always included unpublished data.
She acknowledges that many systematic reviews, even outside USPSTF, do not include unpublished data from regulators and manufacturers, but points to research by Erick Turner, a psychiatrist and former FDA reviewer, highlighting the dangers of omitting unpublished data.
Albert Siu, immediate past chair of the task force, defended its reliance on published data, saying peer review "can address many sources of potential bias and methodological limitations." Although others reject this logic.
Lenzer also points to USPSTF's outsourcing of evidence reviews to evidence based practice centres (EPCs), which she says "raises questions of whether financial conflicts could affect task force recommendations."
Although The BMJ found that both USPSTF members and the individual EPC researchers selected to work on reviews were almost entirely free of financial conflicts, several EPCs receive industry funding, raising questions of potential institutional conflicts of interest.
Finally, some experts contacted by The BMJ said that the USPSTF's advice for depression screening will lead to inappropriate treatment. Allen Frances, a well known critic of overdiagnosis, told The BMJ that current services for severely mentally ill people were already strained to bursting point, saying "we don't need to create an army of mislabeled healthy people."
Others say that before making population based screening and prevention recommendations, independent researchers should analyse more forms of raw data such as clinical study reports and patient level data - and when such rigorous analyses are not possible it is important to acknowledge the resulting uncertainty.
"What we need are fewer recommendations and more high quality evidence to base decisions on," argues Carl Heneghan, professor of evidence based medicine at the University of Oxford. "Currently we seem to be seeing the exact opposite."
Lenzer included a similar review of the task force recommendation on statins for primary prevention of heart disease.
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Journal
The BMJ